The DestDefaults enumeration specifies the various types of action that will be taken on behalf of the user for a drag destination site.

• DestDefaultMotion: If set for a widget, GTK+, during a drag over this widget will check if the drag matches this widget's list of possible targets and actions. GTK+ will then call Graphics.UI.Gtk.Gdk.Drag.dragStatus as appropriate.
• DestDefaultHighlight: If set for a widget, GTK+ will draw a highlight on this widget as long as a drag is over this widget and the widget drag format and action are acceptable.
• DestDefaultDrop: If set for a widget, when a drop occurs, GTK+ will will check if the drag matches this widget's list of possible targets and actions. If so, GTK+ will call Graphics.UI.Gtk.Gdk.Drag.dragGetData on behalf of the widget. Whether or not the drop is successful, GTK+ will call Graphics.UI.Gtk.Gdk.Drag.dragFinish. If the action was a move, then if the drag was successful, then True will be passed for the delete parameter to Graphics.UI.Gtk.Gdk.Drag.dragFinish
• DestDefaultAll: If set, specifies that all default actions should be taken.

Packing parameters of a widget

• The Packing parameter determines how the child behaves in the horizontal or vertical way in an Graphics.UI.Gtk.Layout.HBox or Graphics.UI.Gtk.Layout.VBox, respectively. PackNatural means the child is as big as it reqests. It will stay at the start of the end of a Graphics.UI.Gtk.Layout.Box if there is more space available. All children packed with PackRepel will be padded on both sides with additional space. PackGrow will increase the size of a widget so that it covers the available space. A menu bar, for instance, should always stay at the top of a window and should only occupy as little space as possible. Hence it should be packed at the start of a Graphics.UI.Gtk.Layout.VBox with the packing option PackNatural. The working area of a window (e.g. the text area in an editor) should expand when the window is resized. Here the packing option PackGrow is the right choice and it is irrelevant whether the main area is inserted at the start or the end of a box. Finally PackRepel is most useful in a window where no widget can make use of excess space. Examples include a dialog box without list boxes or text fields.

Resize mode, for containers

• ResizeParent Pass resize request to the parent
• ResizeQueue Queue resizes on this widget
• ResizeImmediate Perform the resizes now

Mode in which selections can be performed

• There is a deprecated entry SelectionExtended which should have the same value as SelectionMultiple. C2HS chokes on that construct.

The TargetFlags enumeration is used to specify constraints on an entry in a Graphics.UI.Gtk.Gdk.Selection.TargetList. These flags are only used for drag and drop.

• If the TargetSameApp flag is set, the target will only be selected for drags within a single application.
• If the TargetSameWidget flag is set, the target will only be selected for drags within a single widget.

Used in Graphics.UI.Gtk.Genearl.Drag.DragContext to indicate what the destination should do with the dropped data.

• ActionDefault: Initialisation value, should not be used.
• ActionCopy: Copy the data.
• ActionMove: Move the data, i.e. first copy it, then delete it from the source.
• ActionLink: Add a link to the data. Note that this is only useful if source and destination agree on what it means.
• ActionPrivate: Special action which tells the source that the destination will do something that the source doesn't understand.
• ActionAsk: Ask the user what to do with the data.

Keyboard modifiers that are depressed when the user presses a key or a mouse button.

• This data type is used to build lists of modifers that were active during an event.
• The Apple key on Macintoshs is mapped to Alt2 and the Meta key (if available).
• Since Gtk 2.10, there are also Super, Hyper and Meta modifiers which are simply generated from Alt .. Compose modifier keys, depending on the mapping used by the windowing system. Due to one key being mapped to e.g. Alt2 and Meta, you shouldn't pattern match directly against a certain key but check whether a key is in the list using the elem function, say.

Information on from what level of the widget hierarchy the mouse cursor came.

NotifyAncestor

The window is entered from an ancestor or left towards an ancestor.

NotifyVirtual

The pointer moves between an ancestor and an inferior of the window.

NotifyInferior

The window is entered from an inferior or left towards an inferior.

NotifyNonlinear

The window is entered from or left towards a window which is neither an ancestor nor an inferior.

NotifyNonlinearVirtual

The pointer moves between two windows which are not ancestors of each other and the window is part of the ancestor chain between one of these windows and their least common ancestor.

NotifyUnknown

The level change does not fit into any of the other categories or could not be determined.